Only wanting contact

A cursory search of some available resources didn't turn up the reference I was looking for, but I remember coming across several references to an older study that found that patrons who had received service from a reference librarian who managed to touch their hand during the interaction (while handing them a slip of paper perhaps) consistently rated the service they received as better than those in a control group who received the same service, but did not have their hand touched during the interaction.

When I've come across it, the results have been mentioned generically to highlight just how powerfully important touch is (usually in self-helpy type literature). I can't say I've ever seen mention of this in library literature.

So my question though is (if the results are not apocryphal), should/can we be explicitly incorporating what was learned from this study into the service we are providing at the library (after all the study was supposedly performed with reference librarians!).

More clearly, should we be making subtle, imperceptable efforts to make hand-to-hand contact (of course no grabbing etc) with those we are serving in the course of the reference interview where appropriate?

Can this be formulated as an organizational procedure - to touch hands where appropriate? Is that somehow too "dangerous" to make a directive? Or is this somehow only something those in the know could only do under the radar?